Piston seal for single incision surgery

ABSTRACT

A surgical portal apparatus for use during a minimally invasive procedure includes a housing and a portal member extending distally from the housing. The housing and portal member combination defines a longitudinal axis. The portal member is sized to be positioned within tissue and has an opening at the distal end. The apparatus also has a pliable seal and a plurality of concentrically arranged piston members, disposed within the housing. The pistons are engageable with the pliable seal and are adapted for moving relative to the housing to control the diameter of a passage through the inner portion of the seal in response to the insertion of a surgical object.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims the benefit of and priority to U.S.Provisional Application Ser. No. 61/081,473 filed on Jul. 17, 2008, theentire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a device, and a method of use thereof,for facilitating access to a patient's internal cavities during asurgical procedure. More particularly, the present disclosure relates toa surgical apparatus adapted for insertion into an incision in tissue,and for the sealed reception of one or more surgical objects, so as toform a substantially fluid-tight seal with both the tissue and thesurgical object, or objects.

2. Background of the Related Art

Today, many surgical procedures are performed through small incisions inthe skin, as compared to the larger incisions typically required intraditional procedures, in an effort to reduce trauma to the patient andrecovery time. Generally, such procedures are referred to as“endoscopic”, unless performed on the patient's abdomen, in which casethe procedure is referred to as “laparoscopic”. Throughout the presentdisclosure, the term “minimally invasive” should be understood toencompass both endoscopic and laparoscopic procedures. During a typicalminimally invasive procedure, surgical objects, such as surgical accessdevices, e.g., trocar and trocar assemblies, or endoscopes, are insertedinto the patient's body through one or more incisions in tissue.

In general, prior to the introduction of the surgical object into thepatient's body, insufflation gasses are used to enlarge the areasurrounding the target surgical site to create a larger, more accessiblework area. Accordingly, the maintenance of a substantially fluid-tightseal about the surgical object, or objects, is important, so as toprevent the escape of the insufflation gases and the deflation orcollapse of the enlarged surgical work area.

To this end, various apparatus, including valves, seals and the like,are used during the course of minimally invasive procedures and arewidely known in the art. However, a continuing need exists for anapparatus and associated seal for insertion in tissue that canaccommodate a variety of differently sized surgical objects whilemaintaining the integrity of an insufflated workspace.

SUMMARY

Accordingly, the present disclosure provides a surgical portal apparatuswith a seal assembly, which will allow a surgeon to efficaciouslyutilize instruments of varying diameter in a surgical procedure. Thesurgical portal apparatus includes a longitudinal opening to permitpassage of a surgical object through the surgical portal apparatus. Thisseal assembly obviates the need for multiple adapters to accommodateinstruments of varying diameters by providing a seal with an adjustableopening. One embodiment is directed to a surgical portal apparatushaving a housing, a portal member, a pliable seal, and a plurality ofconcentrically arranged pistons for use within the housing. The portalmember extends from the housing, having a longitudinal axis definedtherethrough. The portal member is dimensioned for positioning withintissue and defining an opening at a distal end. The piston members areengageable with the inner portions of the pliable seal and are adaptedfor movement relative to the housing to automatically control thediameter of the passage in response to insertion of a surgicalinstrument.

Each of the plurality of piston members acts upon the inner portions ofa pliable seal. Each of the plurality of piston members is retained in arespective channel within the housing. The channels are configured torestrict movement of piston members in a radial direction. As theplurality of piston members are moved toward the center of the passage,the dimensioning of the passage is reduced. Each of the plurality ofpiston members is capable of moving independently of each other. Theseal is fully open in the “at rest” position and is capable of fullyclosing to prevent the escape of fluid when activated. A duck-bill sealor zero seal may be used in conjunction to aid in preventing the escapeof fluid during insertion and extraction of a surgical object.

The piston members are movable in response to the introduction of asurgical object to establish a substantial sealing relationship with thesurgical object. Movement is accomplished by an actuation mechanismacting upon the piston members, which in turn act against the pliableseal to decrease the diameter of the passage. The actuation mechanismincludes a motor with resistive circuitry. The resistive circuitry isconfigured to detect an increased load on the motor and stops the motorwhen a specific load is detected. The motor releasably holds the loadtorque on the piston members in the second relative position causing aconstant seal with the surgical object.

The surgical portal apparatus includes a sensor positioned within thehousing. Located distal to the piston seal, the sensor adapted to beengaged by the surgical object during introduction of the surgicalobject within the housing. Engagement of the sensor activates the motorand thereby causes the movement of the piston members of the pistonseal, from the first relative position to the second relative position.The sensor is capable of determining location and size of the insertedsurgical object and moves the plurality of piston members accordingly.

In another embodiment, the surgical portal apparatus includes a manualactuation mechanism mounted to the housing and operatively connected tothe plurality of piston members of the piston seal. A clinician engagesand manipulates the manual actuation mechanism to selectively move theplurality of piston members between the first and second relativepositions. In still another embodiment, the actuation mechanism includesan electromagnetic repulsion system capable of moving the plurality ofpiston members.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosure,and together with a general description of the disclosure given above,and the detailed description of the embodiments given below, serve toexplain the principles of the disclosure.

FIG. 1 is a right, perspective view of a trocar assembly and a sealassembly in accordance with the principles of the present disclosure;

FIG. 2 is a left, perspective view of a trocar assembly and a sealassembly in accordance with the principles of the present disclosure;

FIG. 3 is rear, perspective view of a trocar assembly and a sealassembly in accordance with the embodiment of FIGS. 1-2;

FIG. 4 is a side, cross-sectional view of a trocar and seal assembliesin accordance with the present disclosure;

FIG. 5 is a side, cross-sectional view of a piston member for use withthe trocar and seal assemblies in accordance with the embodiment ofFIGS. 1-4;

FIG. 6 is a top, partial internal view of the trocar and seal assembliesin accordance with the embodiment of FIG. 4;

FIG. 7 is a top view in accordance with the embodiment of FIG. 4;

FIG. 8 is a side, cross-sectional view of the trocar and seal assembliesin accordance with the present disclosure;

FIG. 9 is a top, internal view of the trocar and seal assemblies inaccordance with the embodiment of FIG. 8;

FIG. 10 is a top view in accordance with the embodiment of FIG. 8; and

FIG. 11 is a flow chart illustrating one method of operation of thetrocar assembly in accordance with the present disclosure.

Other features and advantages of the present disclosure will becomeapparent from the following detailed description, taken in conjunctionwith the accompanying drawings, which illustrate, by way of example, theprincipals of the present disclosure.

DETAILED DESCRIPTION

The seal assembly of the present disclosure provides a substantial sealbetween a body cavity of a patient and the outside atmosphere before,during, and after insertion of an instrument through a trocar assembly.Moreover by providing a fluid tight seal with each instrument wheninserted, the seal assembly of the present disclosure is capable ofaccommodating instruments of varying diameters, e.g., from about 5 mm toabout 15 mm. The flexibility of the present seal assembly greatlyfacilitates endoscopic surgery especially wherein a variety ofinstruments having differing diameters are often interchanged during asingle surgical procedure.

The seal assembly contemplates the introduction and manipulation ofvarious types of instrumentation, adapted for insertion through a trocarand/or trocar assembly, while maintaining a fluid tight interface aboutthe instrumentation to preserve the atmospheric integrity of a surgicalcavity from gas and/or fluid leakage. Specifically, the presentlydisclosed seal assembly substantively eliminates introduction andremoval forces upon a surgical object relative to the seal housing axisand automatically adjusts the seal to compensate for off-center movementof the implement relative to the housing thereby minimizingcontamination and leakage from the body cavity. Examples ofinstrumentation contemplated for use with the present disclosure includeclip appliers, graspers, dissectors, retractors, staplers, laser probes,photographic devices, endoscopes and laparoscopes, tubes, and the like.Such instruments will be collectively referred to herein as “surgicalobjects”.

Referring now to the drawings, in which like reference numerals identifyidentical or substantially similar parts throughout the several views,FIGS. 1-2 illustrate a seal assembly 100 in accordance with oneembodiment of the present disclosure mounted to a trocar assembly 200.Trocar assembly 200 may be any conventional trocar suitable for theintended purpose of accessing a body cavity and permit introduction ofinstruments therethrough. Trocar assembly 200 is particularly adaptedfor use in laparoscopic surgery where the peritoneal cavity isinsufflated with a suitable gas, e.g., CO₂, to raise the cavity wallfrom the internal organs therein. Trocar assembly 200 is typically usedwith an obturator assembly (not shown) which is a sharp pointedinstrument positionable within the passageway of the trocar assembly200. The obturator assembly is utilized to penetrate the abdominal walland then is subsequently removed from the trocar assembly 200 to permitintroduction of the surgical instrumentation utilized to perform theprocedure.

With reference to FIGS. 1-2, trocar assembly 200 includes trocar sleeve202 and trocar housing 204 mounted to an end of the sleeve 202. Anymeans for mounting trocar sleeve 202 to trocar housing 204 areenvisioned including threaded arrangements, bayonet coupling, snap-fitarrangements, adhesives, etc. Trocar sleeve 202 and trocar housing 204may also be integrally formed. Trocar sleeve 202 defines a longitudinalaxis “a-a” extending along the length of sleeve trocar 202. Trocarsleeve 202 further includes an internal longitudinal passage 206,defined therein and dimensioned to permit passage of surgicalinstrumentation, therethrough. An aperture 212 is defined adjacent thedistal end of trocar sleeve 202, which extends through the wall of thetrocar sleeve 202. In the following description, as is traditional theterm “proximal” refers to the portion of the instrument closest to theoperator while the term “distal” refers to the portion of the instrumentremote from the operator.

Aperture 212 permits passage of insufflation gases through trocar sleeve202 during the surgical procedure. Trocar sleeve 202 may be formed ofstainless steel or other rigid materials such as a polymeric material(or the like) and may be clear or opaque depending upon a particularpurpose. The diameter of trocar sleeve 202 may vary, but, typicallyranges from about 10 mm to about 15 mm for use with the seal assembly100 of the present disclosure. Trocar housing 204 includes a portopening 214 defined therein, which is configured to receive luer fitting216 therein (See FIGS. 1, 2, and 4). Luer fitting 216 is adapted forconnection to a supply of insufflation gas and incorporates valve 218,which selectively opens and closes the passage of the luer fitting 216to regulate the flow of insufflation gas into the peritoneal cavity.

With continued reference to FIGS. 1-4, seal assembly 100 will bediscussed in detail. Seal assembly 100 may be a separate component fromtrocar assembly 200 and, accordingly, may be adapted for releasableconnection to the trocar assembly 200. Alternatively, seal assembly 100may be integrally incorporated as part of trocar assembly 200 forming asingle unit. Seal assembly 100 includes a seal housing, having a pistonseal 104 disposed therein. Seal housing 102 is generally dimensioned tohouse the various internal cooperating components of the sealingassembly 100. Seal housing 102 also defines central seal housing axis“b-b” which is preferably parallel to the axis “a-a” of trocar sleeve202 and, more specifically, coincident with the axis “a-a” of the trocarsleeve 202. Seal housing 102 incorporates two housing components,namely, first and second housing components 106 and 108, respectively,which, when assembled, form the seal housing 102.

As shown in FIG. 4, first housing component 106 defines inner orproximal guide wall 112 and outer cylindrical wall 114, disposedradially outwardly therefrom. Proximal guide wall 112 defines a centralpassage 116, which is configured to laterally confine an instrument (notshown) within the seal housing 102. Proximal guide wall 112 furtherincludes a flexible seal member 118 moveably disposed thereon andpositioned to automatically engage an outer shaft or a surgicalinstrument upon insertion into central passage 116 as explained in moredetail below. Outer wall 114 surrounds proximal guide wall 112 andextends distally therefrom.

Second housing component 108 of the seal housing 102 includes atransverse wall 122 and a cylindrical portion 124. Cylindrical portion124 is dimensioned to mate with the outer wall 114 of first housingcomponent 106, as best shown in FIG. 2.

Referring now to FIGS. 3-5, a piston seal 104 is mounted between thefirst housing component 106 and second housing component 108. Theassembled components are held together by a series of screws or other,positive fastening means extending through circumferentially-disposedholes. Piston seal 104 includes a plurality of piston members 126 eachincluding a piston body 128, a tapered leading edge 130, and an aft end132. (See FIG. 5) The plurality of piston members 126 are anchoredwithin the seal housing 102, in a series of channels 146 that surroundthe periphery of the central passage 116. As the plurality of pistonmembers 126 are actuated, a force is applied to the outer most end ofeach of the plurality of piston members 126 causing each of theplurality of pistons members 126 to move within the channels 146. Themovement of the plurality of seal members 126 forces the seal member 118to move between a first relative position and a second relativeposition.

Flexible seal member 118 may be fabricated from a single suitableelastomeric material having sufficient resiliency to stretch and form aseal about an inserted objected. Suitable materials include, but are notlimited to polyurethane and copolyester. To minimize friction theelastomeric materials may be coated with silicon, the productpolytetrafluoroethylene sold under the trademark TEFLON®, or the like.

The plurality of piston members 126 may be fabricated from any rigidmaterial, including but not limited to plastic, metal, or composite. Theplurality of piston members 126 may also be fabricated from a variety ofdifferent materials, e.g., the piston body 128 being made from a plasticmaterial and the tapered leading edge 130 being made from a compositematerial. To minimize friction, the plurality of piston members 126and/or channels 146 may be made from or coated with a low frictionmaterial.

Prior to the insertion of a surgical instrument, the piston seal 104 isbiased in an open orientation with the seal assembly 100 resting in afirst position relevant to the proximal guide wall 112. Upon theinsertion of a surgical instrument, the plurality of piston members 126automatically moves from the first position to a second positionrelative to the proximal guide wall 112. The plurality of piston membersare substantially closer to one another. The plurality of piston members126 move automatically and, preferably, simultaneous, to encapsulate andengage the outer shaft of the surgical instrument and form a sealtherearound. Instruments of varying diameters may be selectivelyinserted and withdrawn from the trocar without interrupting orcompromising the integrity of the surgical cavity. The relative size anddimension of the central passage 116 automatically adjusts and regulatesto adapt to surgical instrumentation of various sizes.

The actuation mechanism 110 moves the piston seal 104 between the firstrelative, or open position, and the second relative position engagingthe surgical instrument to establish a sealing relation therewith or toclose the piston seal 104. The actuation mechanism 110 may include amotor 134 (See FIG. 4) having an associated switch 140, which regulatesthe operation of the plurality of piston members 126 the switch 140 maybe an “on/off” switch, which (when placed in the “on” position)configures the piston seal 104 for automatic engagement of a surgicalinstrument's shaft. The motor 134 may be any suitable miniature electricmotor which may be battery powered. The motor output is operativelyconnected to the plurality of piston members 126 of piston seal 104 in amanner to effect linear movement of the piston members 126 between thefirst and second relative positions. Various electrical connections forconnecting the plurality of piston members 126 to the motor 134 areenvisioned and appreciated by one skilled in the art.

The force on the outer shaft of the surgical instrumentation may beapplied by one or more resilient springs 150. The springs 150 may beconfigured to extend relative to proximal guide wall 112 at differentdistances to accommodate off-center insertion or movement of thesurgical instrument within the surgical cavity, e.g., some of theplurality of piston members 126 may travel a greater distance withinchannel 146 than some of the other plurality of piston members 126relative to a respective proximal guide wall 112. In this instance, someof the plurality of piston members 126 react against the surgicalinstrument without much travel while some of the plurality of pistonmembers 126 are allowed to travel greater distances in order to contactthe surgical instrument. The resilient springs 150 also act as guides tokeep the plurality of pistons members 126 properly aligned.

The motor 134 may also be controlled by the interaction between thesurgical instrumentation and a switch 140. As the inserted instrumentcontacts the switch 140, the switch 140 is triggered and activates themotor 134. The motor 134, in turn, applies a force via the actuationmechanism 110 to the plurality of piston members 126. For example, inone embodiment, a motor 134 acts upon the ramp member 138 to cause rampmember 138 to rotate in a given direction. As the ramp member 138rotates, the force from the motor 134 is translated through theresilient spring 128 to the piston members 126, causing the plurality ofpiston members 126 to move between relative positions. As ramp member138 rotates clockwise the piston seal 104 closes and when the rampmember 138 rotates counterclockwise the piston seal 104 opens. Rampmember 138 may include a scalloped or textured outer surface 138 a (SeeFIG. 3), which is dimensioned for a gripping engagement by the user tofacilitate rotation.

A sensor 152 may be employed in place of a switch to regulate andcontrol the movement of the plurality of piston members 126 for engagingand disengaging the surgical instrumentation. The sensor 152 istypically located at a position that is distal to the piston seal 104within the seal housing 102 such that as the surgical instrument isintroduced into the center passage 116, the surgical instrument engagesthe sensor 152. Once engaged, the sensor 152 activates the motor 134causing the piston seal 104 to constrict around the surgical instrument.Thus, the plurality of piston members 126 move from a first relativeposition to a second relative position. The sensor 152 may be configuredto interact with a central process unit to determine which of theplurality of piston members 126 are actuated and the degree ofactuation. Once the surgical instrument is removed from the centralpassage 116, sensor 152 reactivates and the plurality of piston members126 reset back to the first position to allow the surgical instrument tobe removed without damage to the piston seal or requiring substantialforce and which maintains the integrity of the surgical cavity.

Resistive circuitry 136 may be utilized to determine the desired oracceptable load place upon the outer shaft of the surgical instrument bythe plurality of piston members 126. For example, when the motor 134operates, the motor 134 draws an electrical current that can be measuredby resistive circuitry 136 associated with the motor 134. It isenvisioned that other alternative uses of resistive circuitry may beimplemented to measure the load upon the motor 134. Once a specific,predetermined load is detected by the resistive circuitry 136, the motor134 stops, which in turn stops the plurality of piston members 126 inthe second relative position and holds the plurality of piston members126 against the instrument shaft.

Although a motor 134 is disclosed as part of the actuation mechanism110, it is appreciated that the actuation mechanism 110 may be manuallyoperated by a clinician. There are several ways a clinician can causethe linear movement of the plurality of piston members 126 and activatethe piston seal 104. One way is to manually rotate the ramp member 138by the scalloped outer surface 138 a. Another alternative is a manuallever connected to an actuation mechanism reacting upon the pistonsthrough various linkages (not shown).

In another embodiment, as shown in FIG. 8, the actuation mechanism 110includes an electromagnetic repulsion system 148. In this instance, atleast two magnets are used in each piston channel 146 a first magnet142, having a first magnetic polarity, is attached to the piston member126 and a second magnet 144 is attached to the wall 124 opposite thepiston shaft end with a repelling magnetic polarity pointing towards thefirst magnetic polarity. As magnet 144 is electrically energized, magnet142 is forced away from the wall 124, causing the piston seal 104 tomove from the first relative position to the second relative position.

While the invention has been particularly shown, and described withreference to the preferred embodiments, it will be understood by thoseskilled in the art that various modifications and changes in form anddetail may be made therein without departing from the scope and spiritof the invention. Accordingly, modifications such as those suggestedabove, but not limited thereto, are to be considered within the scope ofthe invention.

1. A surgical portal apparatus, comprising: a housing; a portal memberextending from the housing and having a longitudinal axis definedtherethrough, the portal member dimensioned for positioning withintissue and defining an opening; a pliable seal having inner sealportions defining a seal passage for reception of a surgical instrumentintroduced within the opening, the inner seal portions dimensioned forestablishing a substantial seal about the surgical instrument; aplurality piston members within the housing, the piston members beingengageable with the inner seal portions of the seal defining the sealpassage, and adapted for movement relative to the housing to causecorresponding movement of the inner seal portions and thereby control adimension of the seal passage; and, a motor operatively coupled to thepiston members and actuable to move the piston members.
 2. A surgicalportal apparatus as defined in claim 1, further comprising: a pluralityof channels defined within the housing, each channel dimensioned andadapted to accommodate a corresponding piston member, the channels beingconfigured to restrict movement of the pistons in a radial direction. 3.A surgical portal apparatus as defined in claim 1, wherein the pistonmembers are dimensioned and adapted to move independently relative toone another.
 4. A surgical portal apparatus as defined in claim 1,including resistive circuitry associated with the motor and beingadapted to detect an increased load on the motor to thereby releasablesecure the motor in an actuated orientation.
 5. A surgical portalapparatus as defined in claim 1, further comprising: at least one sensorpositioned within the housing, the sensor adapted to measure the sizeand location of the surgical object during introduction of the surgicalobject within the passage of the housing, to the senor operable coupledto the actuation mechanism to regulate the movement of the plurality ofpiston members based on information from the sensor.
 6. A surgicalportal apparatus as defined in claim 1, wherein the pliable sealincludes a proximal seal face and a distal seal face, and defines achannel between the proximal seal face and the distal seal face, thechannel at least partially accommodating the piston member.
 7. Asurgical portal apparatus as defined in claim 6, wherein the pistonmembers are adapted for radial movement within the channel and relativeto the longitudinal axis between a first unactuated position and asecond actuated position.
 8. A surgical portal apparatus as defined inclaim 7, including a switch operatively connected to the motor, theswitch being actuable to actuate the motor.
 9. A surgical portalapparatus as defined in claim 7, wherein the switch is dimensioned andadapted to be manually actuated.
 10. A surgical portal apparatus asdefined in claim 7, wherein the switch is dimensioned and positioned tobe engaged by the surgical instrument upon introduction within theopening of the portal member.
 11. A surgical portal apparatus as definedin claim 1, wherein the inner seal portions are dimensioned tointerconnect the proximal seal face and the distal seal face.
 12. Asurgical portal apparatus as defined in claim 1, including a sensorpositioned to detect at least one of a dimension or location of thesurgical object to control operation of the motor to thereby regulatemovement of the piston members.
 13. A surgical portal apparatus asdefined in claim 12, wherein the resistive circuitry is adapted to stopoperation of the motor upon detection of a predetermined load thereonwherein the piston members are secured in the second actuated position.14. A surgical portal apparatus as defined in claim 1, includingresistance circuitry associated with the motor and adapted for detectionan increased load on the motor to thereby control operation of themotor.
 15. A surgical portal apparatus, comprising: a housing; a portalmember extending from the housing, the housing and the portal memberdefining a longitudinal axis and having a longitudinal passageway forreception of a surgical object within tissue; a single pliable sealhaving inner portions defining a seal opening for reception of thesurgical object in substantial sealed relation therewith; a plurality ofpiston members within the housing, the piston members being adapted forat least radial movement from a first initial position to a secondactuated position to move the inner seal portions defining the sealopening in a radial inward direction to reduce a dimension of the sealopening; an actuation mechanism operatively connected to the pistonmembers and being actuable to cause movement of the piston memberstowards the second actuated positions; and a sensor operatively coupledto the actuation mechanism and adapted to detect one of dimension orlocation of the surgical object, and cooperate with the actuationmechanism to control movement of the piston members between the firstinitial and second actuated positions.
 16. A surgical portal apparatusas defined in claim 15, wherein the actuation mechanism includes anelectromagnetic repulsion system for actuating the plurality of pistonmembers.